This invention relates to a device for accumulating electrical energy composed of a winding of superimposed strips. The invention also relates to a method for producing a device for accumulating electrical energy composed of a winding of superimposed strips.
The invention applies preferably, but not exclusively, to the production of capacitors of electrochemical type.
Production of capacitors through spiral winding of a plurality of strips of different materials which are preferably superimposed has been known for a long time. Conventionally, two of the strips are of electrically conducting material so as to constitute the two electrodes of the capacitor, and these strip electrodes are each connected by at least one collector element at an electrical connection terminal outside the capacitor.
The windings thus produced are generally of substantially cylindrical shape, generated by rotation or flattened, and have a substantially cylindrical lateral face and two opposite end faces.
These windings are generally covered by a protective sheathing made of an electrically insulating material and to which electrical connection terminals are fixed.
As described in U.S. Pat. No. 4,633,369 for making up collector elements that connect the electrodes to terminals of a capacitor obtained by winding strips or sheets. Known is offsetting the two strip electrodes with respect to a median plane orthogonal to the winding in such a way that after winding, each strip has, at right angles to one of the end faces of the winding, an edge which is free by the amount of the offsetting.
The amount of offsetting is selected in such a way that a metallic element can be crimped, clamped or soldered onto the conducting part formed at each end of the capacitor, and thereby constitute a collector element which itself can be connected to an electrical terminal of the said capacitor.
This technical solution is satisfactory with respect to efficiency of the connection and the section that is established for the current to pass through, but since it is cumbersome, it has serious drawbacks.
An object of the invention is to propose a device for accumulating electrical energy made up of a winding of superimposed strips which does not have the aforementioned drawbacks.
To this end, the invention has as its subject matter a device for accumulating electrical energy comprising a substantially cylindrical winding of strips, at least one of which is an electrical strip conductor, this device being defined transversally by a substantially cylindrical lateral face and longitudinally by two opposite end faces which each include an edge of the said electrical strip conductor. This device is characterized in particular in that at least one of the edges of at least one electrical strip conductor contains a plurality of teeth disposed in such a way that on at least one of the end faces of the device they form at least one set in which they are substantially superimposed in a predetermined direction, approximately perpendicular to a plane tangent to the cylindrical face of the said device, so as to constitute a group of elements of electrical connection to a terminal and in which each element extends in continuity with the electrical strip conductor which comprises it.
The invention also has as its subject matter a method of producing a device of the aforementioned type.